anticoagulant

A drug that interferes with blood
clotting, used to treat or prevent thrombosis
and clot embolism. The two main types of
anticoagulants are heparin, which is injected
and has an immediate but short-lived effect, and the commarins (including
warfarin) which are taken by mouth and are longer-lasting. They affect different
parts of the clotting mechanism, commarins depleting factors in the liver.